Polymer grouting method for constructing multi-wing pile

ABSTRACT

A polymer grouting method for constructing multi-wing pile, includes steps of: (1) arranging the positions of piles; (2) producing multi-wing drilling tool and locating holes; (3) installing grouting pipes; (4) polymer lifting grouting; (5) forming polymer multi-wing piles. According to the geologic characteristics, the three-wing drilling tool or the four-wing drilling tool are produced through pressing the drilling tool into each location of pile by a static pressure equipment to form the multi-wing holes, and injecting two-component expansive polymer materials to the holes, wherein the polymers expand and solidify after reacting for filling the holes and the gaps in the soil of slope to be fully integrated with the surrounding soil and form the polymer multi-wing piles.

BACKGROUND OF THE PRESENT INVENTION

1. Field of Invention

The present invention relates to a field of slope protection andlandslide control, and more particularly to a polymer grouting methodfor constructing multi-wing pile relating to a field of slope protectionof roads and landside control.

2. Description of Related Arts

Geological disasters occur frequently in China, wherein the number ofdead and missing caused by geological disasters accounts for about ⅓ ofthe total number of disasters, and the cost of direct economic loss areas high as billions of dollars, wherein landslide is the geologicaldisaster which occurs most frequently and is most harmful, wherein thenumber thereof is 50%-60% of the total number of geological disasters.Once the landslide disasters occur, traffic is interrupted, channels arecongested, factories are destroyed, and villages are buried, seriouslife and property loss and environmental damage are caused. In recentyears, with the rapid development of economic construction and humanengineering activities in China, the frequency and scale of thelandslide disasters increase year by year, it is a serious threat topeople's lives and property and the production of industry andagriculture. Therefore, the prevention and control of landslide disasterand the active exploration of new material, new technology and newequipment in landslide disaster treatment have become important tasks tobe solved.

Landslide is a phenomenon of rock and soil overall sliding along one ormore weakness surfaces of slope under the action of gravity. The factorsof inducing the landslide are various, wherein the geological structureand physic-mechanical property of the rock and soil on slope are theinternal causes, wherein rainfall, underground water level change, andhuman engineering activities are the external causes. The formationprocess of landslide is the result of interaction.

Aiming at the factors of inducing the landslide, 5 ways of conventionaltreatments of landslide comprise: removing the rock and soil oflandslide, establishing drainage project, improving the rock and soil onslope, reducing pressure and establishing retaining project. It iseconomical for the small scale landslides to remove the rock and soil oflandslide through the excavation work but not the big scale landslides;establishing drainage project is an indirect control measure, whereinunderground water and surface water are guided to the natural channelsthrough building drainage and cut-off system at the inside and outsideof the landslide respectively for avoiding landslide caused by that therock and soil of slope is weakened when encountering water and itsstrength is sharply dropped down; improving the rock and soil on slopeis also an indirect control measure, wherein the properties of the rockand soil on slope are improved by electro-osmosis, calcinations, andchemical grouting to increase the strength and anti-sliding ability;reducing pressure is a way which unloads at the top of the slope andloading at the bottom of the slope for decreasing the strength, forimproving the anti-sliding force and the stability of slope, wherein itis suitable to the small and medium scale landslides, and the design andconstruction are simple but it is only used in earthwork, wherein thepre-condition for using is the mechanical equipments are easy to bestationed in the construction plant, or the labor intensity is high andthe efficiency is low; wherein establishing retaining project is a waywhich increases the anti-sliding ability through building the retainingstructure to stabilize the rock and soil of slope. The common forms ofretaining wall comprise anti-sliding retaining walls, pre-stressedanchor rods (or anchor cables) and anti-sliding piles. Anti-slidingretaining walls are positioned at a bottom of the slope, it is suitableto treat the slopes which is small-scale and has small sliding thrust;pre-stressed anchor rods (or anchor cables) are used in reinforcing rockslopes but it is hard to used in reinforcing soil slopes; anti-slidingpiles are widely used in treating different scales of slopes.

Among the ways of conventional treatments of landslide, establishingretaining project is the most effective and direct, and the earthquantity is smallest, wherein anti-sliding piles are favored byengineers because of the characters such as great anti-sliding, flexiblepile position and strong applicability. The pile body of anti-slidingpiles goes deeply into the slope through a sliding surface, wherein alandslide thrust is passed to the stable formation by the combination ofpile and surrounding rock and soil, wherein the landslide thrust isbalanced by the effect of anchoring and passive resistance to improvethe state of landslide and stabilize the landslide.

Anti-slide piles comprise driven piles, bored piles and digging pilesaccording to the method of construction, wherein anti-slide pilescomprise timber piles, steel piles, and reinforced concrete pilesaccording to the material, wherein the shapes of section can becircular, tubular and rectangular. Anti-slide piles have manysignificant advantages such as: (1) high anti-slide capacity, which hasmore obvious advantage than the retaining wall which resists the slideforce under an action of gravity through a resistance produced byembedding the piles into stable layer; (2) flexible pile position, whichcan be set at the position which is the most anti-sliding, wherein itcan be used individually or be combined with the retaining structuresuch as anchor rods and anchor cables, wherein the huge landslide can becut into several units to treat separately when the anti-slide piles areset in lines; (3) strong applicability, which can be used in differentscales and types of slide treatment; (4) checking the geology directlythrough digging the pile holes to modified the original design.

Though the advantages of anti-slide piles are outstanding, there arestill some shortcomings which are hard to overcome with respect to thedemand of landslide treatment, comprising: (1) large disturbance to theslopes when digging the holes by machines or human, wherein thelandslide state is easy to worsen especially when using the drivenpiles; (2) complicated process, slow construction speed, high laborintensity and low efficiency, wherein mud and concrete retaining wall isneeded when using machines to dig holes, wherein it is hard to meet thedemand of emergency rescue; (3) large equipments, high energyconsumption and poor applicability, wherein it is hard to enter and setup the machines in the steep slope engineering; (4) long constructionperiod, huge material consumption and high cost; (5) poor durability oftimber piles and steel piles, and large difference between theelasticity modulus of the reinforced concrete piles and soil, whereinthe reinforced concrete piles and soil are easy to cracked because ofthe low deformation coordination; (6) polluting the environment becausea number of effluent and waste are produced in the cement concrete pileconstruction process.

Therefore, anti-slide piles are most widely used in landslide treatment,but there are still some shortcomings which are hard to overcome withrespect to the current demand of landslide prevention and control,comprising: large disturbance to the slopes, long construction period,high cost and complicated process. Thus, developing new materials, newtechnologies and new equipments of landslide disaster treatment whichare efficient and cheap are of great importance to prevent and controllandslide disaster and protect people's lives and property.

Polymer grouting technology is the foundation reinforcement techniquequickly developed in the 1970s. It reinforces the foundation and fillsthe gaps through grouting polymers to the foundation, wherein thepolymers expand and solidify after reacting. At present, polymergrouting technology is widely used in the foundation reinforcement ofindustrial and civil structures, wherein the polymer grouting method forconstructing multi-wing pile has not been used to treat landslide inChina.

SUMMARY OF THE PRESENT INVENTION

Aim to the shortcomings of landslide treatment specially that high cost,low construction speed and large disturbance to slopes which are hard tomeet the demand of emergency rescue, the present invention is to providea polymer grouting method for constructing multi-wing pile which iseasy, cheap, safe and environmental protecting. The present invention isto provide an advanced, efficient, safe and suitable method to achievethe landslide treatment.

Accordingly, in order to accomplish the above objects, the presentinvention provides a polymer grouting method for constructing multi-wingpile, comprising the steps of:

-   -   (1) arranging positions of piles, comprising: arranging the        positions on a slopes which need be treated according to design;    -   (2) producing a multi-wing drilling tool and locating multi-wing        holes, comprising: producing drilling tool and press the        drilling tool for an expected depth to form the multi-wing holes        at each location of pile according to the design;    -   (3) installing grouting pipes, comprising: installing grouting        pipes in the multi-wing holes, wherein the grouting pipes are        provided at centers of the multi-wing holes, wherein outlets of        grouting pipes are provided at bottoms of the multi-wing holes;    -   (4) polymer lifting grouting, comprising: providing a grouting        control equipment for lifting polymer on tops of the multi-wing        holes, providing the grouting pipes into a pipe fixing device of        the grouting control equipment for lifting polymer, injecting        two-component expansive polymer materials through the grouting        pipes of the polymer grouting system into the multi-wing holes,        and turning on the grouting control equipment for lifting        polymer at the same time; and    -   (5) forming polymer multi-wing piles, comprising: lifting the        grouting pipes according to a set rate, wherein the polymer        materials expand and solidify after reacting for filling the        multi-wing holes and gaps in the soil of slope to be fully        integrated with the surrounding soil and form the polymer        multi-wing piles.

In step (2), the multi-wing drilling tool is combined with a drill stemand wings welding on a circumference of the drill stem, wherein adiameter D of cone probe of the drill stem is 40-80 mm, wherein thewings of the drill stem are triangular steel plates welding blades,wherein a highness H of the wings is 100-400 mm, an angle α between abase of the wings and the drill stems is 30-45 degrees, a thickness T ofthe wings is 10-30 mm.

The multi-wing drilling tool comprises a three-wing drilling tool and afour-wing drilling tool.

According to the geologic characteristics of project, the three-wingdrilling tool and the four-wing drilling tool are produced. Throughpressing the drilling tool into each location of pile to form themulti-wing holes, and injecting two-component expansive polymermaterials into the multi-wing holes, the polymers expand and solidifyafter reacting for filling the multi-wing holes and the gaps in the soilof slope to fully integrated with the surrounding soil and form thepolymer multi-wing piles with strong anti-slide ability.

Compared with conventional technology of anti-slide piles, the presentinvention has the advantages comprising:

-   -   (1) Non-water reaction, which has high applicability; it is        suitable to be used in the landslide disaster rescue for the        different scales of landslide because of the polymer multi-wing        piles which can be constructed rapidly to form an anti-sliding        retaining structure system. The non-water reacted polymer does        not shrink, which has great tensile, anti-vibrating and        anti-crack properties, wherein the volume expansion rate is        large, the shape of pile can fulfill the multi-wing holes,        wherein it is not only suitable to the soil and the slope        protection but also the landslide treatment which the cement        base is not suitable to;    -   (2) high anti-pulling and anti-shearing; the contact area        between the pile and surrounding soil of polymer multi-wing pile        is bigger than the pile that the section is circle or rectangle        which improves the anti-pulling and the anti-shearing;    -   (3) small disturbance to slope; the disturbance to slope is        small to the slope through pressing the drilling tool into each        location of pile to form the multi-wing holes and anhydrous        reacting;    -   (4) fast constructing, no need to be cured; the construction is        fast because of the continuous operation of drilling and        lifting; About 90% of the strength is formed after the reaction        of material for 15 minutes;    -   (5) low cost; the cost of polymer multi-wing pile technology can        save 50% of the cost compared with the conventional anti-sliding        technology;    -   (6) easy constructing; the series of polymer grouting equipment        can be used in different construction plants, the stationing is        convenient and the power consumption is small;    -   (7) great durability; the polymer grouting material has stable        property, non-pollution, good flexibility, closely combined with        the rock and soil of the slope, compatible deformation, small        osmotic coefficient, great resistance to chemical corrosion and        anti-penetrability performance when being buried underground for        a long time.

Therefore, the present invention has serious advantages in the landslidetreatment. The polymer grouting method for constructing multi-wing pileis a newer set of technologies compared with the conventionaltechnology, mainly in:

-   -   (1) the aspect of the material of pile and the idea of        pile-forming, wherein non-water reacted polymer grouting        materials are used in the polymer grouting method for        constructing multi-wing pile, according to the idea of flexible        pile-forming, which is safe, environmental protecting and light,        and has high expansion rate, great anti-permeability and early        strength. The polymer multi-wing piles are flexible, firmly        gluing with the soil, wherein the deformation is harmonious, the        properties of anti-permeability and anti-crack are great;    -   (2) the aspect of the mechanism of treatment, wherein the        polymers expand and solidify after reacting for filling the        multi-wing holes and the gaps in the soil of slope to be fully        integrated with the surrounding soil and form the polymer        multi-wing piles to realize rapidly stabilizing the sliding        slope;    -   (3) the aspect of the mode of construction, wherein polymer        multi-wing piles are formed through pressing the drilling tool        into each location of pile by a static pressure equipment and        polymer lifting grouting method to form the multi-wing holes,        which realizes a easy construction, wherein it achieves rapid        landslide treatment and small disturbance to the slope;    -   (4) the aspect of the shape of pile, comprising: substituting        the shape which is circle or rectangular for the shape which is        multi-wing pile, which improves the anti-pulling and the        anti-shearing ability thereof.

Therefore, there are obvious differences between the invention and theconventional anti-sliding pile technology according to the aspect of thematerial of pile and the idea of pile-forming, the aspect of themechanism of treatment, the aspect of the mode of construction, and theaspect of the shape of pile, wherein it has the advantages of greatadaptability, fast speed, light weight, high tenacity, cheap cost anddurable in use, and has a great development prospect in economy andsocial benefit.

These and other objectives, features, and advantages of the presentinvention will become apparent from the following detailed description,the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical view of a multi-wing drilling tool.

FIG. 2 is a top view of the multi-wing drilling tool.

FIG. 3 is a schematic diagram of pressing the drilling tool into eachlocation of pile to form the multi-wing holes.

FIG. 4 is a schematic diagram of polymer lifting grouting.

FIG. 5 is a section view of a polymer multi-wing pile.

FIG. 6 is a top view of the polymer multi-wing pile.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A polymer grouting method for constructing multi-wing pile according toa preferred embodiment of the present invention is illustrated,comprises the steps of:

-   -   (1) arranging positions of piles, comprising: arranging the        positions on slope which need be treated according to design;    -   (2) producing a three-wing drilling tool and locating the holes,        comprising: producing the three-wing drilling tool 1, the        three-wing drilling tool 1 is combined with a drill stem 1-1 and        three wings 1-2 welding on a circumference of the drill stem        1-1, wherein a diameter D of cone probe of the drill stem 1-1 is        40-80 mm, wherein the diameter D of cone probe can be 40 mm, 50        mm, 65 mm, 75 mm, or 80 mm, wherein the wings 1-2 are triangular        steel plates welding blades, wherein a highness H of the wings        1-2 is 100-400 mm, wherein the highness H of the wings 1-2 can        be 100 mm, 200 mm, 350 mm, or 400 mm, i.e., any value between        100-400 mm, wherein an angle α between a base of the wings 1-2        and the drill stem 1-1 is 30-45 degrees, a thickness T of the        wings 1-2 is 10-30 mm, wherein an angle β between two adjacent        wing 1-2 of the three-wing drilling tool 1 is 120 degrees,        wherein the three-wing drilling tool 1 are pressed into each        location of pile for an expected depth by a static pressure        equipment 2 to form three-wing holes 3 according to the design;    -   (3) installing grouting pipes, comprising: installing grouting        pipes 4 in the three-wing holes 3, wherein the grouting pipes 4        are provided at a center of the three-wing holes 3, wherein        outlets of the grouting pipes 4 are provided at a bottom of the        three-wing holes 3;    -   (4) polymer lifting grouting, comprising: providing a grouting        control equipment 5 for lifting polymer on a top of the grouting        pipes 4, providing the grouting pipes 4 into a pipe fixing        device of the grouting control equipment 5 for lifting the        polymer, injecting two-component expansive polymer materials 6        through the grouting pipes 4 of the polymer grouting system into        the three-wing holes 3, and turning on the grouting control        equipment 5 for lifting polymer at the same time;    -   (5) forming polymer three-wing piles, comprising: lifting the        grouting pipes according to a set rate of 8 cm/s, wherein the        two-component polymer materials expand and solidify after        reacting for filling the three-wing holes and the gaps in the        soil of slope to be fully integrated with the surrounding soil        and form three-wing polymer piles 7.

The grouting method of polymer multi-wing according to another preferredembodiment of the present invention is illustrated, comprises the stepsof:

-   -   (1) arranging positions of piles, comprising: arranging the        positions on slope which need be treated according to design;    -   (2) producing a four-wing drilling tool and locating the holes,        comprising: producing the four-wing drilling tool 1, the        four-wing drilling tool 1 is combined with a drill stem 1-1 and        four wings 1-2 welding on a circumference of the drill stem 1-1,        wherein a diameter D of cone probe of the drill stem 1-1 is        40-80 mm, wherein the diameter D of cone probe can be 40 mm, 50        mm, 65 mm, 75 mm, or 80 mm, wherein the wings 1-2 are triangular        steel plates welding blades, wherein a highness H of the wings        1-2 is 100-400 mm, wherein the highness H of the wings 1-2 can        be 100 mm, 200 mm, 350 mm, or 400 mm, i.e., any value between        100-400 mm, wherein an angle α between a base of the wings 1-2        and the drill stem 1-1 is 30-45 degrees, a thickness T of the        wings 1-2 is 10-30 mm, wherein an angle β between two adjacent        wings 1-2 of the four-wing drilling tool 1 is 90 degrees,        wherein the four-wing drilling tool 1 are pressed into each        location of pile for an expected depth by a static pressure        equipment 2 to form four-wing holes 3 according to the design;    -   (3) installing grouting pipes, comprising: installing grouting        pipes 4 in the four-wing holes 3, wherein the grouting pipes 4        are provided at a center of the four-wing holes 3, wherein        outlets of the grouting pipes 4 are provided at a bottom of the        four-wing holes 3;    -   (4) polymer lifting grouting, comprising: providing a grouting        control equipment 5 for lifting polymer on a top of the grouting        pipes 4, providing the grouting pipes 4 into a pipe fixing        device of the grouting control equipment 5 for lifting the        polymer, injecting two-component expansive polymer materials 6        through the grouting pipes 4 of the polymer grouting system into        the four-wing holes 3, and starting the grouting control        equipment 5 for lifting polymer at the same time;    -   (5) forming polymer four-wing piles, comprising: lifting the        grouting pipes according to a set rate of 8 cm/s, wherein the        two-component polymer materials expand and solidify after        reacting for filling the four-wing holes and the gaps in the        soil of slope to be fully integrated with the surrounding soil        and form four-wing polymer piles 7.

One skilled in the art will understand that the embodiment of thepresent invention as shown in the drawings and described above isexemplary only and not intended to be limiting.

It will thus be seen that the objects of the present invention have beenfully and effectively accomplished. Its embodiments have been shown anddescribed for the purposes of illustrating the functional and structuralprinciples of the present invention and is subject to change withoutdeparture from such principles. Therefore, this invention includes allmodifications encompassed within the spirit and scope of the followingclaims.

What is claimed is:
 1. a polymer grouting method for constructingmulti-wing pile, comprising steps of: (1) arranging positions of piles,comprising: arranging said positions on slopes which need be treatedaccording to a design; (2) producing a multi-wing drilling tool andlocating multi-wing holes, comprising: producing said multi-wingdrilling tool and press said multi-wing drilling tool for an expecteddepth to form said multi-wing holes at each location of pile accordingto said design; (3) installing grouting pipes, comprising: installingsaid grouting pipes in said multi-wing holes, wherein said groutingpipes are provided at a center of said multi-wing holes, wherein outletsof said grouting pipes are provided at a bottom of said multi-wingholes; (4) polymer lifting grouting, comprising: providing a groutingcontrol equipment for lifting polymer on a top of said multi-wing holes,providing said grouting pipes into a pipe fixing device of said groutingcontrol equipment for lifting polymer, injecting two-component expansivepolymer materials through said grouting pipes of said polymer groutingsystem into said multi-wing holes, and turning on said grouting controlequipment for lifting polymer at the same time; (5) forming polymermulti-wing piles, comprising: lifting said grouting pipes according to aset rate, wherein said polymer materials expand and solidify afterreacting for filling said multi-wing holes and gaps in said soil ofslope to be fully integrated with a surrounding soil and form saidpolymer multi-wing piles.
 2. The polymer grouting method forconstructing multi-wing pile, as recited in claim 1, wherein, in step(2), said multi-wing drilling tool is combined with a drill stem andmulti-wings welding on a circumference of said drill stem, wherein adiameter D of cone probe of said drill stem is 40-80 mm, wherein saidmulti-wings are triangular steel plates welding blades, wherein ahighness H of said multi-wings is 100-400 mm, wherein an angle α betweena base of said multi-wings and said drill stem is 30-45, wherein athickness T of said multi-wings is 10-30 mm.
 3. The polymer groutingmethod for constructing multi-wing pile, as recited in claim 2, whereinsaid multi-wing drilling tool comprises a three-wing drilling tool and afour-wing drilling tool.